Clinical and angiographic results of transluminal extraction coronary atherectomy in saphenous vein bypass grafts

Abstract

Background: Transluminal extraction coronary (TEC) atherectomy is a relatively new device that has recently been approved by the Food and Drug Administration. Because of its ability to aspirate clot and atheromatous material, TEC atherectomy may be useful in patients with stenoses in saphenous vein bypass grafts.

Methods and results: TEC atherectomy was performed on 158 saphenous vein graft lesions in 146 consecutive patients with a mean age of 65 +/- 8 years (78% men). Clinical indications for atherectomy included stable angina (37%), unstable angina (54%), and postinfarction angina after recent (< 1 month) myocardial infarction (8%). Patients with acute myocardial infarction and target vessels < 2 mm in diameter were excluded. The mean age of the bypass graft was 8.3 +/- 3.0 years, and 17% were diffusely diseased and degenerated. Complex lesion morphology included total occlusion (6%), eccentricity (64%), ulceration (18%), and thrombus (28%). The TEC atherectomy cutter was successfully advanced through 144 lesions (91%), but technical failures occurred in 14 lesions (9%), and these were subsequently managed by successful balloon angioplasty. Quantitative angiography revealed an increase in lumen diameter from 0.9 +/- 0.5 mm, to 1.5 +/- 0.7 mm after TEC atherectomy, to 2.3 +/- 0.8 mm after percutaneous transluminal coronary angioplasty (PTCA) (P < .001), which corresponded to decreases in diameter stenosis from 75 +/- 14%, to 58 +/- 20% after TEC atherectomy, to 36 +/- 22% after PTCA (P < .001). Device success was achieved in 39.2% (post-TEC atherectomy decrease in diameter stenosis > or = 20%), and procedural success was achieved in 84% (final diameter stenosis < 50% in the absence of a major complication). Angiographic complications were evident in 33 lesions (20.7%) immediately after TEC atherectomy and in 8 lesions (5%) after PTCA, including distal embolization (11.9%), no-reflow (8.8%), and abrupt closure (5.0%), but no perforations. Adjunctive PTCA (and other medical therapy) successfully managed 61% of angiographic complications. Serious clinical complications included in-hospital death in 3 patients (2.0%), emergency bypass surgery in 1 patient who died (0.7%), Q wave myocardial infarction in 3 patients (2.0%), non-Q wave myocardial infarction in 4 patients (2.7%), vascular injury requiring surgical repair and/or blood transfusion in 9 patients (6.1%), and hemorrhagic cerebral infarction in 4 patients (2.7%). Using a composite clinical end point defined as in-hospital death, emergency bypass surgery, or myocardial infarction, the strongest independent correlate (P < .001) of a severe clinical complication was the development of one or more serious angiographic complications (no-reflow, distal embolization, or abrupt closure) immediately after TEC atherectomy. Complete clinical follow-up was available in 118 (92%) of 128 eligible patients at an interval of 6.0 +/- 2.5 months after discharge. Late cardiac outcome included recurrent angina treated with medical therapy (18%), repeat percutaneous intervention on the original target lesion (26%), repeat coronary artery bypass surgery (5%), Q wave myocardial infarction (4%), and late cardiac death (7%). Angiographic follow-up in 105 (80%) of 132 eligible lesions revealed a restenosis rate of 69% (defined as a diameter stenosis > 50%), including 30 lesions (29%) with total occlusion of the original lesion.

Conclusions: In patients with stenoses in saphenous vein bypass grafts, TEC atherectomy is limited by the frequent need for adjunctive balloon angioplasty to achieve adequate lumen enlargement and to manage TEC atherectomy-induced complications. Although the incidence of serious clinical complications is similar to that of other percutaneous interventions in vein grafts, there is a high incidence of restenosis and late vessel occlusion. Prospective randomized studies are needed to determine the best revascularization strategy for high-risk patients with old degenerated vein